MONDAY, Feb. 28 (HealthDay News) -- Many American women
abandoned hormone replacement therapy after a 2002 study found the
treatment was tied to higher breast cancer risk. A sharp drop in
breast cancer incidence among whites was observed soon after.
However, a new study suggests that the 2002-2003 decline in
breast cancer incidence among white women did not continue through
The data suggests that the drop in breast cancers linked to
women abandoning hormone replacement therapy (HRT) has now bottomed
Breast cancer rates among U.S. white women fell by about 7
percent between 2002 and 2003 after the release in 2002 of findings
from the Women's Health Initiative study that linked HRT with an
increased risk of breast cancer.
To examine whether that trend has continued, American Cancer
Society and U.S. National Cancer Institute (NCI) researchers
reviewed breast cancer data collected from 2000 to 2007 by NCI
Surveillance, Epidemiology and End Results (SEER) registries across
The analysis revealed that the sharp decline in breast cancer
rates among white women that occurred between 2002 and 2003 did not
continue between 2003 and 2007. Instead, breast cancer rates among
white women remained relatively stable from 2003 to 2007.
"Postmenopausal hormone replacement therapy certainly had accounted for an increase in the incidence of developing a breast cancer. The use of postmenopausal HRT had sharply declined after multiple reports proved this relationship," noted one expert, Dr. Sharon M. Rosenbaum-Smith, a breast cancer specialist and surgeon at the Comprehensive Breast Center at St. Luke's-Roosevelt Medical Center in New York City.
"As more women stop using HRT, and less women start it after reaching menopause, it would be expected that the incidence [of breast cancer] would plateau at some point," she said. "This study is promising in that it has not shown an increase in the incidence of breast cancer, and the stopping of HRT use can certainly be a contributing factor to this plateau."
The new report notes, however, that the 2002-2003 trend only
showed up among white women: there was no major decrease in breast
cancer rates among black and Hispanic women between 2002 and 2003,
and no significant changes in breast cancer rates for those groups
of women from 2003 to 2007.
According to the ACS/NCI study authors, there are a number of
possible factors that could explain the leveling out of breast
cancer rates among white women in recent years:
- The decrease in HRT use after 2003 may not have been large
enough to continue delaying breast cancer diagnoses.
- The trends may reflect improved sensitivity of mammography
without the influence of HRT, since HRT increases breast density
and compromises the diagnostic performance of mammograms and breast
- Breast cancer rates may reflect the relatively stable rates of
screening mammography in the United States since 2000. An increase
in screening rates would have likely been associated with an
increased number of breast cancer diagnoses.
The study was released online in advance of publication in a
future print issue of the journal
Cancer Epidemiology, Biomarkers & Prevention.
The U.S. National Cancer Institute has more about
menopausal hormone replacement therapy and